497 DIFFERENTIAL ROLE OF OPIOID RECEPTORS IN TIBIAL NERVE INHIBITION OF NOCICEPTIVE AND NON-NOCICEPTIVE BLADDER REFLEXES IN CATS

Abstract

You have accessJournal of UrologyBladder and Urethra: Anatomy, Physiology and Pharmacology II1 Apr 2012497 DIFFERENTIAL ROLE OF OPIOID RECEPTORS IN TIBIAL NERVE INHIBITION OF NOCICEPTIVE AND NON-NOCICEPTIVE BLADDER REFLEXES IN CATS Abhijith Mally, Jeffrey Larson, P. Dafe Ogagan, Changfeng Tai, Bing Shen, Jicheng Wang, James Roppolo, and William C. de Groat Abhijith MallyAbhijith Mally Pittsburgh, PA More articles by this author , Jeffrey LarsonJeffrey Larson Pittsburgh, PA More articles by this author , P. Dafe OgaganP. Dafe Ogagan Pittsburgh, PA More articles by this author , Changfeng TaiChangfeng Tai Pittsburgh, PA More articles by this author , Bing ShenBing Shen Pittsburgh, PA More articles by this author , Jicheng WangJicheng Wang Pittsburgh, PA More articles by this author , James RoppoloJames Roppolo Pittsburgh, PA More articles by this author , and William C. de GroatWilliam C. de Groat Pittsburgh, PA More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2012.02.567AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Electrical stimulation of somatic afferent pathways in the tibial nerve can inhibit bladder activity and therefore aid in the management of overactive bladder symptoms. Opioid peptides have a well known role in controlling pain mechanisms and are involved in somatic afferent inhibition of non-nociceptive bladder reflexes. We hypothesized that inhibition of irritation-induced bladder overactivity by tibial nerve stimulation could be due to activation of opioid receptors. We used naloxone to block the opioid receptors and assess the receptor function during tibial neuromodulation. METHODS Naloxone was administered to 20 cats in increasing cumulative doses. Saline (n=10) or .25% acetic acid (n=10) were utilized to irritate the bladder and induce overactivity. Bladder capacity and the degree of inhibition of bladder activity induced by tibial nerve stimulation were assessed by cystometrogram. RESULTS Infusion of acetic acid (AA) significantly reduced bladder capacity compared to saline. During CMG, tibial nerve stimulation (TNS) significantly inhibited bladder contraction and increased bladder capacity by 41.5±9.9% and 46.1±7.9% of the saline control capacity. Naloxone completely eliminated TNS inhibition of bladder overactivity. Naloxone did not change bladder capacity during AA irritation. However, during saline infusion, naloxone significantly reduced bladder capacity to 66.5±8.1% of the control capacity. During saline infusion TNS induced an acute increase in bladder capacity and an increase that persisted following stimulation. Naloxone administered during the post-stimulation inhibition still decreased bladder capacity. CONCLUSIONS These results indicate that opioid receptors have different roles in modulation of bladder reflexes induced by nociceptive and non-nociceptive stimuli and in somatic afferent inhibition of these reflexes, raising the possibility that opioid receptors may be a target for pharmacological treatment of lower urinary tract disorders. © 2012 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 187Issue 4SApril 2012Page: e204 Advertisement Copyright & Permissions© 2012 by American Urological Association Education and Research, Inc.MetricsAuthor Information Abhijith Mally Pittsburgh, PA More articles by this author Jeffrey Larson Pittsburgh, PA More articles by this author P. Dafe Ogagan Pittsburgh, PA More articles by this author Changfeng Tai Pittsburgh, PA More articles by this author Bing Shen Pittsburgh, PA More articles by this author Jicheng Wang Pittsburgh, PA More articles by this author James Roppolo Pittsburgh, PA More articles by this author William C. de Groat Pittsburgh, PA More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...